ABSTRACT
A new condyle can be reconstructed by osteodistraction, but the biomechanical properties of the neocondyle remain unknown. This study examined the hypothesis that the biomechanical properties of neocondylar cancellous bone could reach control levels 24 weeks after its creation by osteodistraction. The right mandibular condyles were removed and reconstructed by osteo-distraction in 16 adult goats. Their contralateral condyles served as controls. Microstructural and mechanical properties were examined by microcomputed tomography and mechanical testing. At 24 weeks after distraction, the neocondyle grew larger in size, but the shape and histological features were similar to those of the controls. The cancellous bone of the neocondyle even appeared to be more dense and stiffer in comparison with the control condyle. The results of this study suggest that the neocondyle created by osteodistraction develops nearly normal biomechanical properties for functional loading by 24 weeks after creation.
Subject(s)
Bone Regeneration/physiology , Mandibular Condyle/physiology , Osteogenesis, Distraction/methods , Range of Motion, Articular/physiology , Animals , Biomechanical Phenomena , Bone Density/physiology , Compressive Strength , Goats , Male , Mandibular Condyle/surgery , Mandibular Condyle/ultrastructure , Plastic Surgery Procedures/methods , Statistics, Nonparametric , Temporomandibular Joint/physiology , Temporomandibular Joint/surgery , Temporomandibular Joint/ultrastructureABSTRACT
This study investigated the possibility of achieving osseointegration of implants placed in a distracted site during the consolidation period. Four healthy male mongrel dogs were used in this experiment. A subperiosteal corticotomy around the mandible was performed between the left mandibular premolar and first molar. After a 7-day latency period for soft tissue healing, the distraction was performed at the rate of 1 mm per day for 14 consecutive days to allow for 14 mm of elongation, using an extraoral distraction device. Three weeks after the completion of distraction, screw-type implants were placed in the distracted site. Twenty-four weeks after placement of the implants, they were stable, and osseointegration had been achieved physically, radiographically, and histologically. These results suggest the possibility of shortening the period of implant treatment by using the distraction osteogenesis technique.
